generator



Nov. 21, 1961 H. |=v ROST ET AL SYSTEM AND MEANS FOR DETERMINATIONOEDISTANCE AND DIRECTION Original Filed June 6, 1950 2 Sheets-Sheet lPULSE GENERATOR WW w rr vi Nov. 21, 1961 H. F. Ros-r ET AL 25,090

SYSTEM AND MEANS FOR DETERMINATION OF DISTANCE AND DIRECTION OriginalFiled June 6, 1950 2 Sheets-Sheet 2 SAVTOOTH I GENERA rok PUL 5' EGENERATOR .AHPL lF/ER.

I AMPLIFIER H United States Patent ()fifice 25,090 SYSTEM AND MEANS FORDETERMINATION OF DISTANCE AND DIRECTION Helge Fabian Rost, deceased,late of Bylgiavagen 5,

Djursholm, Sweden, by Svenska Handelsbanken, ad-

ministrator, Stockholm, and Per Harry Elias Claesson,

Danderyd, Sweden; said Svenska Handelsbanken assiguor to Bjorn GustavAlexander Rost, Anders Erik Rost, and Nils Helge Erland Rost, all ofVallingby, Stockholm, Sweden 7 Original No. 2,648,062, dated Aug. 4,1953, Ser. No.

137,074, Jan. 6, 1950. Application for reissue Aug. 22,

1960, Ser. No. 14,160. In Sweden Feb. 26, 1948 9 Claims. (Cl. 343-11)Matter enclosed in heavy brackets appears in the original patent butforms no part of this reissue specification; matter printed in italicsindicates the additions made by reissue.

The present application is a continuation-in-part of our co-pendingapplication Ser. No. 360,362, filed October 9', 1940, now Patent No.2,536,770.

The said patent pertains to a radio object detecting system comprising asource of frequency modulated radio frequency energy, means fordirecting radioenergy in the form of a beam, means for causing said beamto scan a region proximate to said system in a cyclic manner, means forreceiving the beam energy reflected by an object upon which it impinges,and for directly deriving energy from said radiating means and combiningit with said reflected energy, means for frequency analysing the saidcombined energies, and means including a cathode ray tube connected tothe scanning means and to the frequency analysing means, which arejointly controlled for producing a visual signal, which indicatessimultaneously the direction and the distance of the reflecting object.

waves from about the same direction as the transmitted source for theemission of rays projectible as visible light spots on said screen,deviation means adapted to deviate such a ray radially, and controlmeans coupled to the receiving means for the control of the intensity ofthe ray, and synchronizing means coupled to the movable partsof theantenna means and to said saw-tooth generator and to the said deviationmeans for rotating the ray synchronously with the directional antennameans and for deviating the ray in the same instant direction as that ofthe antenna means, whereby a pulse is transmittable simultaneously asthe ray leaves its normal position in the direction of a reflectingobject, and a light spot is produced on the screen at a distance fromits normal position proportional to the distance to said reflectingobject upon the receipt of a reflected wave.

According to this invention a particularly eifective arrangement isobtained, whereby the transmitting means is modulated with a pulsegenerator and the indicating ray is modulated with a saw-toothgenerator, which in known manner are synchronized with each other. Inthis manner the transmitter can be modulated with very short ReissuedNov. 21, 1961 and heavy pulses, which, however, are not suitable for themodulation of the ray-deviating means in a cathode ray tube.

Our invention will be better understood from the following description,when read in connection with the accompanying drawings, in which:

FIG. 1 shows a modification of the diagram shown in FIG. 2 of saidPatent'Number 2,536,770, in which the wave analyser 112 and variablecondenser 113 have been replaced by an amplifier 112, and alternator 24driven by motor 19 has been replaced by a saw-tooth generator 124 and apulse generator 125, which are synchronized andcoupled to each other.

FIG. 2 is similar to FIG. 1 with the exception that the same radiantelements are used both for transmission and reception, shifting means126 having been provided for shifting between transmission andreception.

In FIG. 1 a radio transmitter 1 provided with a sharply directed antennameans 3, preferably of ultra short wave type, and a modulator 2 areattached to a rotatable axis 16. A detector 4 provided with a sharplydirected antenna means 5 is attached to the same rotatable axis 16 forreceiving radio waves transmitted by the transmitter and reflected by anobject in space.

Collector rings 74 and 75 are arranged on the axis 16 for conductingcurrent to circular resistance wires or potentiometers 76 and 77arranged on the axis 16 and provided with brushes 80-81 and 78-79respectively. Con.- ductors from the collector rings 74 and 75 areconnected to the resistance wires 76 and 77 at diametrically oppositeplaces, whereby a diameter through points 84--85 on wire 76 is locatedat right angles to a diameter through points 8283 on wire 77.

The axis 16 isdriven by a motor 19 and worm gear 1718. A pin 114 isattached to the cogwheel 18. An arm 115 is provided with an opening-orslot for moving the pin 114 back and forth, if cogwheel 18 iseccentrically located with respect to axis 16.

A cathode ray oscillograph is provided with two deflecting plates 104coupled to brushes 7879 of resistance wire 77. k

Two other deflecting plates 103 at right angles to the first mentioneddeflecting plates 104 are connected to brushes 80--81 of resistance wire76. The resistance wires 76 and 77 are interconnected in a circuit fordeflection of the cathode ray in such a manner, that the indicating rayon the fluorescent screen 102 will have exactly the same direction asthe antenna means of the transmitter 1 and of the receiver 4, or. as thecommon antenna means shown in FIG. 2 for both transmitting andreceiving.

A cathode ray trap diaphragm 105 is provided in the path of the cathoderay and electrodes 106 for deviation of the ray, when no reflectionradio energy is received, so that the ray is normally invisible on thescreen 102. The cathode ray tube is further provided with an anode 107,a cathode 108, afilament 109 and a current source 110 for supplyingnegative potential to the electrodes to cause the ray to hit thediaphragm 105, instead of proceeding along the axis of the tube througha center hole in the diaphragm.

An anode current source 111 is connected to the anode 107. An amplifier112 of known construction is connected between the receiver 4 and thecathode ray tube, and an extra amplifier 49 can be interconnected forfurther amplification of the reflected pulses. If desired, the amplifier49 can also be adapted to act as a rectifier.

124125 is a pulse emitting device comprising a pulse generator 125connected to the modulator 2 of the transmitter 1, and a saw-toothgenerator 124 coupled to the 3 ray deviating means 103104 over circularresistance wires 7677.

The pulse generator and the saw-tooth generator are connected with eachother and synchronized for emitting heavy modulating pulses to thetransmitter and for deviating the cathode ray from its origin on thescreen 102 at the moment the radio pulse is transmitted into space.

Instead of separate antennas and directing means. 3 and for thetransmitter and the receiver a common antenna and directing means can beused both for transmission and reception as shown in FIG. 2.

By means of a cam (not shown) driven by the motor 19 shifting of theantenna and the directing means can be made in the shifting means 126 inknown manner at desired intervals between the transmitter and thereceiver.

If the transmitter and the receiver are located on board a movablecraft, they can be combined with a known compensating device for keepingthe axis 16 in a vertical position, for example by -a gyro or otherdevice.

The operation of the device shown in FIGS. 1 and 2 takes place in thefollowing manner.

A pulse modulated wave transmitted from the transmitter 1 is received inthe receiver by the detector 4 after after reflection from an object.The transmitter and the receiver can be given a rotating or a back andforth mo tion by means of the axis 16. After amplification of the wavein the amplifier 112 and, if desired, rectification in amplifier 49, apotential is delivered to electrodes 106 so that the cathode ray isshown on the screen 102. When a pulse is generated by the pulse emittingdevice 124- 125, a heavy pulse is transmitted to the modulator 2 and aweak pulse to the deflecting plates 106-104 for simultaneouslydeflecting the cathode ray.

When an echo is received in the receiver 4, said echo is amplified,whereby it actuates the electrodes 106 of the cathode ray tube aftersuch a time and after the cathode ray has been deflected to such adistance from its normal position on the screen, which corresponds tothe echo-time.

The cathode ray is moved towards the periphery of the screen and will bevisible only when an echo arrives.

If the movement of the axis 16 is made sufliciently rapidly, a lightspot will be visible on the screen each time the radio 'wave passes theobject, and if the fluores- "cent screen has been made with sufiicientdelaying action, "a fixed light spot will indicate the position of aship, an iceberg or the entire coastline will be visible as a map entirescreen.

The motor 19 can either directly or by the aid of a sawtooth generatorsynchronized by the motor make the "cathode ray move radially back andforth between the center and the periphery of the screen of the cathoderay tube. When the motor has a certain angle, the cathode ray will thusbe in the center. At this angle the motor will connect the transmitterfor a short moment over a cain'wheel.

--In this case the same reflector can be used for both transmission andreception as shown in FIG. 2. The cam Wheel of the motor will thenswitch between transmission and reception at the above mentioned angle.7 It is, however, not necessary that the motor takes part in thetransmission. The motor can merely attend to the rotation of thetransmitter and of the receiver and synchronously therewith the rotationof the cathode ray.

If the saw-tooth generator moves the cathode ray between the center andthe periphery of the screen, the current from a synchronously operatingpulse generator can then direct the transmitting pulses.

The connection and disconnection of the transmitter can take place bymeans of a shifting device in the form of an electron tube relayinserted in the sending circuit, in order alternately to disconnect thetransmitter and connect the receiver to the respective circuits. Saidrelays can consist of electron tubes or gas-filled tubes, which normallyhave high negative grid voltage and a high interior resistance, butduring the switching period receives from the saw-tooth generator such agrid potential that the inner resistance is sufliciently lowered, and apulse is emitted to the transmitter. When using such electrontuberelays, switching rates of any desired magnitude can be obtained inpractice.

The axis 16, which carries the transmitter and the receiver can, ofcourse, be made to rotate continuously or reciprocatingly so that onlythe desired region can be observed.

The direction of the desired object, for example, with respect to thetrack of a craft, can according to this invention be obtained by meansof an indicating device combined with the rotating axis, which carriesthe receiver, or combined with an axis driven synchronously with saidaxis.

The fluorescent screen can be provided with a scale using polarcoordinates, whereby the radius of the projection of the ray on thescreen from the origin, indicates the distance to the object. Byobserving the angular position of the ray with respect to the polarcoordinate scale, the angular position of an object with respect to thetrack of a craft can thus be observed.

We claim:

1. A system for the determination of directions and distances to objectsin space comprising, in combination, means for transmitting andreceiving pulse modulated radio waves, highly directional antenna meansfor the transmission of said waves in a certain direction and for thereception of reflected waves from about the same direction as thetransmitted waves, a support, a rotatable shaft on said support, saidantenna means being mounted on said shaft, means to rotate said shaft ata predetermined rate, pulse generating means coupled to the transmittingand receiving means and comprising a saw-tooth generator and a pulsegenerator, circuit means interconnecting said generators with each otherfor maintaining their outputs in predetermined fixed phase relationship,means of indication comprising a ray indicating screen and a rayemitting source for the emission of rays projectable as visible lightspots on said screen, deviation means including deflecting means formoving said ray radially, and control means coupled to the receivingmeans for the control of the intensity of the ray, and synchronizingmeans coupled to the movable parts of the antenna means and to saidsaw-tooth generator and tothe said deviation means for rotating the raysynchronously with the directional antenna means and for deviating theray in fixed angular relationship with respect to the direction of theantenna means, whereby a pulse is transmitted simultaneously as the rayleaves its normal position in the direction of a reflecting object, anda light spot is produced on the screen at a distance from its normalposition proportional to the distance to said reflecting object upon thereceipt of a reflected wave.

2. The system as claimed in claim 1, in which the transmitting andreceiving means are provided with common highly directional antennameans, shifting means connected to said transmitting and receiving meansand to said antenna means and adapted at certain time intervalsalternately to disconnect the transmitting means from and to connect thereceiving means to the said common antenna means and vice versa.

3. A system for the determination of directions and distances to objectsin space comprising, in combination, means for transmitting andreceiving pulse modulated radio waves, highly directional antenna meansfor the transmission of said waves in a certain direction and for thereception of reflected waves from about the same direction as thetransmitted waves, a support, a rotatable vertical shaft on saidsupport, said antenna means being mounted on said shaft, means to rotatesaid shaft at a predetermined rate, pulse generating means coupled tosaid antenna means and comprising a saw-tooth generator and a pulsegenerator, and means whereby said generators are adapted to besynchronized with each other, means-of indication comprising a rayindicating fluorescent screen with delaying action and a ray emittingsource for the emission of rays projectable as visible light spots onsaid screen, deviation means adapted to deviate such a ray radially, andcontrol means coupled to the receiving means for the control of theintensity of the ray, and synchronizing means coupled to the movableparts of the antenna means and to said saw-tooth generator and to thesaid deviation means for rotating the ray synchronously with'thedirectional antenna means and for deviating the ray in the same instantdirection as that of the antenna means, whereby a pulse is transmittedsimultaneously as the ray leaves its normal position in the direction ofa reflecting object, and'a light spot is produced on the screen at alistan'ce from its'normal position proportional to the distance to saidreflecting object upon the receipt of a reflected wave.

4. A direction and distance indicating device of the pulse modulationtype, comprising: supporting means rotatable about a predetermined axis;means for rotating said supporting means; highly directional antennameans carried by said supporting means; transmitting means includingpulse modulating means connected to said antenna means for causing thetransmission of pulse modulated radio waves therefrom; receiving meansconnected to said antenna means for receiving transmitted wavesreflected thereto; a cathode ray device comprising, a retentivefluorescent screen, means for producing a cathode ray which whenunblocked is normally impinging on said screen at a predetermined pointcentrally located thereon, means for deflecting said ray along mutuallyperpendicular axes on said screen passing through said predeterminedpoint, said deflection being independently controllable with respect toeach axis, and means for controlling the intensity of said ray;orienting means connected to said deflecting means and comprising rotarymeans revolving in fixed angular relationship with respect to saidsupporting means for causing said ray to be deflected in a directionfixedly angularly related to the direction of said antenna means; afirst generator for producing potentials of saw tooth wave shapeconnected to said deflecting means and to said orienting means forcyclically increasing the magnitude of said deflection in a linearmanner at a predetermined rate; a second generator connected to saidpulse modulating means and producing pulses of potential controllingsaid transmitting means; a first circuit means interconnecting saidfirst and second generators and causing said second generator to producea pulse at each instant when the output of said first generator causessaid deflecting means to start movement of said ray radially outwardlyfrom said predetermined point on said screen; and a second circuit meansconnecting said receiving means to said intensity control means forproducing a luminous point on said screen upon receipt of a reflectedwave, the angular position of said luminous point being determined bythe direction of said antenna means and the radial distance thereof fromsaid predetermined point being proportional to the total distancetravelled by the transmitted and reflected waves.

5. A device according to claim 4, wherein said cathode ray devicefurther comprises a centrally apertured diaphragm disposed intermediatesaid screen and said deflecting means for blocking said ray in theabsence of any wave received by said receiving means.

6. A device according to claim 4, wherein said orient ing meanscomprises: two spaced circular resistors carried by said supportingmeans concentrically with the axis of rotation thereof; diametricallyopposed points of connection on each resistor, the diameterinterconnecting said points on one resistor being perpendicular to thecorre- 'sponding diameter on the other resistor; diametrically opposedsubstantially coplanar stationary contacts engaging each resistor; andfurther comprising circuit means for connecting said stationary contactsto said deflecting means of said cathode ray tube means; and furthercircui-t means connecting said opposed points of connection on eachresistor to said first generator.

7. A system for the determination of directions and distances to objectsin space comprising, in combination, means for transmitting andreceiving pulse modulated radio waves, highly directional antenna meansfor the transmission of said waves in a certain direction and for thereception of reflected waves from about the same direction as thetransmitted waves, a support, a rotatable vertical shaft on saidsupport, said antenna means being mounted on said shaft for rotationthrough a full 360, means to rotate said shaft at a predetermined rate,pulse generating means coupled to the transmitting and receiving meansand comprising a saw-tooth generator and a pulse generator, circuitmeans interconnecting said generators with each other for maintainingtheir outputs in predetermined fixed phase relationship, means ofindication comprising a ray indicating screen and a ray emitting sourcefor the emission of rays projectable as visible light spots on saidscreen, deviation means consisting solely of a single deflecting meansfor moving said my indication when visible on said screen, from acentral position at the time of transmission of said transmitted wavesradially outwardly toward the periphery of said screen during the timefor reception of the reflected waves, and control means coupled to thereceiving means for the control of the intensity of the ray, andsynchronizing means coupled from the movable parts of the antenna meansand from said saw-tooth generator to the said single deflecting meansfor rotating the ray synchronously with the directional antenna meansand for deviating the ray in fixed angular relationship with respect tothe direction of the antenna means, whereby a pulse is transmittedsimultaneously as the ray leaves its normal central position on thescreen in the direction of a reflecting object, and a light spot isproduced on the screen at a distance from its normal central positionproportional to the distance to said reflecting object upon the receiptof a reflected wave.

8. A system for the determination of directions and distances to objectsin space comprising, in combination, means for transmitting andreceiving pulse modulaled radio waves, highly directional antenna meansfor the transmission of said waves in a certain direction and for thereception of reflected waves from about the some direction as thetransmitted waves, a support, a rotatable shaft on said support, saidantenna means being mounted on said shaft and rotatable through a full360, means to rotate said shaft at a predetermined rate, pulsegenerating'means coupled to the transmitting and receiving means andcomprising a saw-tooth generator and a pulse generator, circuit meansinterconnecting said generators with each other for maintaining theiroutputs in a predetermined fixed phase relationship, means of indicationcomprising a ray indicating scream and a ray emitting source for theemission of rays projectable as visible light spots on said screen,deviation means consisting solely of a single deflecting means formoving said ray indication when visible on said screen, from a centralposition at the time of transmission of said transmitted waves radiallyoutwardly toward the periphery of said screen during the time ofreception of reflected waves, and control means coupled to the receivingmeans for the control of the intensity of the ray, and synchronizingmeans coupled to the movable parts of the antenna means and to saidsaw-tooth generator to the said single deviation means for rotating theray synchronously with the directional antenna means and for deviatingthe ray in fixed angular relationship with respect to the direction ofthe antenna means, whereby a pulse is transmitted simultaneously as theray leaves its normal central position on the screen in the direction:of a reflecting object, and a light spot is produced on the screen at adistance from its normal central position proportional to the distwiceto said reflecting object upon the receipt of a reflected wave.

9, A system for the determination of directions and distances to objectsin space comprising, in combination, means for transmitting andreceiving pulse modulated radio waves, highly directional antenna meansfor the transmission of said waves in a certain direction and for thereception of reflected waves from about the same direction as thetransmitted waves, a support, a rotatable vertical shaft on saidsupport, said antenna means being mounted on said shaft for rotationthrough a full 360, means to rotate said shaft at a predetermined rate,pulse generating means coupled to said antenna means and comprising asaw-tooth generator and a pulse generator, and means whereby saidgenerators are adapted to be synchronized with each other, means-o7indication comprising a ray indicating fluorescent screen with delayingaction and a ray emitting source for the emission of rays projectable asvisible light spots on. said screen, deviation means adapted to deviatesuch a ray radially from a central position'toward the periphery of saidfluorescent screen, and control means coupled to the receiving means forthe control of the intensity of the ray, and synchronizing means coupledto the movable parts of the antenna means and to said saw-toothgenerator and to the said deviation means for rotating the raysynchronously with the directional antenna means and for deviating theray in the same instant direction as that of the antenna means, wherebya pulse is transmitted simultaneously as the ray leaves its normalcentral position on said fluorescent screen in the direction of areflecting object, and a light spot is produced on the screen at adistance from said normal position proportional to the distance to saidreflecting object upon the receipt of a reflected wave.

References Cited in he file of this patent or the origlnal patent UNITEDSTATES PATENTS Australia Sept. 28, 1939

